Thousands of government supporters marched through the capital of Tunisia the day after the funeral of the murdered opposition leader Chokri Belaïd.

About 6,000 supporters of the ruling Ennahda party held a rally in Tunis backing their leader, Rachid Ghannouchi, who was the target of anger from mourners at Friday's funeral of Belaïd, a leftist opposition leader, trade unionist and lawyer.

But the demonstration was dwarfed by the tens of thousands who had turned out in Tunis and other cities to honour Belaïd and to protest against the government on Friday, shouting slogans that included "We want a new revolution".

Belaïd's killing by an unidentified gunman on Wednesday, Tunisia's first political assassination in decades, has plunged the country into shock and soul-searching. It has also highlighted the political stalemate in Tunisia's post-revolutionary transition process, which had been so admired by neighbours such as Egypt and Libya, besieged by their own turmoil.

After Belaïd's death, the prime minister, Hamadi Jebali, promised to form a non-partisan, technocratic cabinet to run the country until an election could take place.

Belaïd's family have accused Ennahda of responsibility for his killing. The party denies any involvement.

After Tunisia's first democratic elections in October 2011, Ennahda became the senior partner in a coalition government with two secular centre-left parties. The temporary national assembly was given a year to draw up a new constitution before setting a date for elections. But several months after the deadline there is still no agreement on a constitution. Some secular MPs from the junior partners have begun to withdraw support; others are demanding Ennahda gives up key cabinet posts. The country's economic situation is worsening, with unemployment officially at 17% but far higher among the young. Lawyers and campaigners say that torture continues in prisons and that the justice system and administration remain corrupt.

Some of the demonstrators shouted "France out" after the French interior minister, Manuel Valls, blamed Belaïd's murder on "Islamic fascism".

Belaïd's death was described in his cortege as a new type of political murder. Under Zine al-Abidine Ben Ali's brutal regime, political opponents and rights campaigners had been imprisoned, tortured, exiled, beaten and intimidated.